(nytimes.com, Jan. 9, Matt Ruff)

In the opening scene of “Beat the Reaper,” the former mob hit man Dr. Peter Brown pauses in the act of disabling a mugger to give readers a paragraph-length tutorial on the architecture of the human arm. Halfway through the paragraph he throws in an asterisk, and in a footnote points out that the lower leg is a lot like the forearm, only less fragile.
First Chapter: ‘Beat the Reaper’ (January 11, 2009) That footnote had me worried. Nothing ruins a story faster than a teller who can’t stay out of the way of his own tale, and for a narrator to interrupt himself in the middle of interrupting himself is usually a very bad sign.

Fortunately, Brown’s creator, the novelist (and doctor) Josh Bazell, is an unusually talented writer. Most of the many digressions in “Beat the Reaper,” his first book, are genuinely entertaining, and the few that don’t work — the footnotes are the most common culprit — annoy primarily because the story is so engaging that you don’t want to be yanked out of it even for the time it takes to glance at the bottom of the page.

Bazell’s protagonist, né Pietro Brnwa, used to be a contract killer for the Mafia, as mentioned. But eight years ago, following a work-­related dispute that involved throwing his best friend out a window, he had a change of heart, entered a witness-protection program and enrolled in medical school. Now he heals people instead of murdering them — although, as the incident with the mugger shows, he hasn’t entirely given up his old ways.

While on his morning rounds, Brown is recognized by a mobster named Eddy Squillante who has been hospitalized with stomach cancer. Squillante’s prognosis is dire, but he’s determined to beat the odds. He offers Brown a simple proposition: keep me alive and I won’t tell your old bosses where you are; let me die (or kill me) and my associates start making phone calls.

Brown’s darkly comic struggle to save Squillante — not just from the cancer, but from the ministrations of a quack surgeon named Friendly — is intercut with highlights from his previous career. This blend of criminal and medical drama works well, and the back-and-forth between timelines keeps things moving.

Bazell has a knack for breathing new life into the most timeworn genre conventions. We learn, for instance, that Brown first became a killer to avenge the murder of his grandparents. Grandma and Grandpa Brnwa weren’t your typical victims, however. Polish Jews, they were survivors of both Auschwitz and, before that, the Bialowieza Forest: “They and a bunch of other newly feral teenagers were hiding out in the snow and trying to kill off enough of the local Jew-hunting parties that the Poles would leave them alone. What this precisely involved they never told me, but it must have been pretty ferocious, because in 1943 Hermann Goering had a lodge at the southern end of Bialo­wieza where he and his guests dressed as Roman senators, and he must have been aware of the situation. There’s also the question of a straggler platoon of Hitler’s Sixth Army that disappeared in Bialo­wieza that winter en route to Stalingrad.”

You can see how a family history like that might incline a guy to take revenge into his own hands. And the unfairness of the deaths — his grandparents survive the ultimate evil, only to be gunned down by a couple of punks from New Jersey — makes it even easier for Brown to make what he later acknowledges is the wrong choice.

The killer with a conscience is another genre staple, and Brown is a fine specimen. Having bludgeoned men to death, he isn’t overly concerned with politeness, and he tends to say exactly what he’s thinking, with charming vulgarity. He’s honest about his character flaws and competent in his actions, except when impulsiveness or his special moral code cause him to act like an idiot. And he has, as you’d expect, a unique way of looking at the world. At one point, while visiting the Polish forest where his grandparents played hide-and-seek with the Nazis, he spies a group of ravens in a tree. He starts thinking about the long-lived nature of parrots and asks himself whether ravens might share it, and whether these same birds might have been here during World War II: “I wondered if my grand­parents had ever tried to eat them.”

It will not be giving too much away to say that Brown’s old employers eventually do learn where he is. The climax of “Beat the Reaper” finds him locked in a medical freezer, waiting for his arch­nemesis to arrive and finish him off. The plan Brown concocts to save himself is the novel’s most original flourish. It is also completely outrageous, so much so that I had to stop and think about whether I could really suspend my disbelief. In the end I decided that, as with the footnotes, Bazell had more than earned my indulgence as a reader. If there’s a better recommendation for a story than that, I don’t know what it is.

Matt Ruff’s novels include “Bad Monkeys,” “Set This House in Order” and “Fool on the Hill.”

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